import turtle as tl
import time

tl.setup(500, 500, 0.0)
tl.penup()
tl.goto(0, 100)
tl.pendown()
tl.pensize(2)
tl.pencolor('red')


a1 = (0, 100)
a2 = (100, 100)
a3 = (100, 0)
a4 = (0, 0)

tl.goto(a2)
tl.goto(a3)
tl.goto(a4)
tl.goto(a1)

tl.penup()
time.sleep(2)

tl.done()
